Animating Extusion

Hello,

I’m a total newbie, but have done some basic animation in Blender and 3DS Max. I’ve done this before, but can’t remember how I did it.

Basically, I’m modeling two air-bags…one on top of the other. When one deflates, the one below it needs to inflate to fill the same space. Then, both need to move upwards.

The movement is not the problem…the problem I can’t figure out is how to make them inflate/deflate during the animation. I’ve tried recording with the mesh tool but whatever mesh changes I make don’t seem to animate. I’m confused here.

Any suggestions would be appreciated!

Thanks!
KDub

You want to make shape keys for this.